The serial makes it a 1939, which could carry either the '36-39 gear set or the '39--48 and beyond. Both would be synchronized on 2 and 3, more modern synchro on the later one.
MANY early Ford V8 transmissions are now hybrids after decades of farmers and hybrids...your case left the Rouge in the 1939 model run, to see what innards it currently has the info is scattered through this old thread:
http://www.jalopyjournal.com/forum/s...ices&showall=1
In the early V8 years engine # prefixes were attached to the whole series of a particular displacement, and the serials ran sequentially throughout.
221's were all 18 prefix, and the series continued growing long past '42 with military engines and then English v8's until 1954!